Re: New problem "next unread" (not sure how new)

[Jack <ostroffjh users sourceforge net>]

Hello Peter,

On 5/17/2017 3:39 PM, Peter Bloomfield wrote:
> Hello Jack:
>
> On 05/15/2017 05:46:42 PM Mon, Jack wrote:
> > I think I started noticing this relatively recently - probably about 
> > the time (or shortly after) the recent set of updates related to 
> > threading.  (git head)  Most of the time I hit the "Next unread" 
> > button (on the toolbar) when all messages in the current mailbox are 
> > read, it does go to an unread message in the next mailbox with any 
> > uread messages.  I actually still haven't paid enough attention to 
> > confirm how it chooses the specific message.  However, sometimes 
> > (fairly consistent by mailbox, I think, but all my mailboxes are 
> > maildir (except inbox)) it goes to the message with the id number one 
> > less than the first unread message.  As we've discussed in the past, 
> > the message id ordering seems to be essentially random, but likely 
> > the order in which the messages are read when scanning (or reading) 
> > the directory.  Is it possible there is an off-by-one thing going 
> > on?  I'd be more certain if it were more consistent.  The reason it's 
> > annoying is that due to the ordering - it sometimes chooses a message 
> > nowhere near the first unread, when ordered by date with JWZ threading.
> >
> > Thanks for any thoughts.
>
> I haven't seen that, as far as I can remember. I have list messages 
> filtered into a Maildir mailbox, and it seems to me that next-unread 
> takes me to an unread message quite reliably. As I recall, when a 
> mailbox is opened, the number of the first unread message, if any, is 
> stored, and that's the message that next-unread takes you to. It's 
> often not the earliest in the current sorting, but it should always be 
> unread. After any message in the mailbox is read, next-unread should 
> go to the next in the current sorting.
Most of the time, I get what you see, but sometimes I get an already 
read message.  Definitely strange.

> You're right that in a Maildir, message numbers do reflect the order 
> in which files are read from the directory, which becomes quite 
> arbitrary over time. Assigning them by age would make better sense, 
> but on the face of it that would require calling stat on each 
> filename, which could add significant overhead; perhaps creation times 
> could be cached between sessions…
>
> Suggestions?
What about finding the first unread in the displayed order, after any 
threading and/or sorting is done.  I don't think any additional file 
access would be necessary, although it might already have been needed to 
do the ordering.

Jack